v3.26.1
Cover
12 Months Ended
Dec. 31, 2025
Document Information [Line Items]  
Document Type 11-K
Entity Central Index Key 0000029989
Entity Registrant Name OMNICOM GROUP INC.
Amendment Flag false
EBP 004 [Member]  
Document Information [Line Items]  
Document Period End Date Dec. 31, 2025